Narrative:

After performing initial cockpit flows and setup; I proceeded to the exterior inspection of my preflight. Upon arriving at the left side of the aircraft; I noticed a small fuel leak. I then proceeded back to the flight deck to notify the captain and have him inspect it too. While looking for the source of the leak; we noticed a small (approximately 1/16 inch) impression in the phenolic panel just inboard of the left inboard trailing edge flap. When the mechanic arrived; he asked us to lower the flaps so he could inspect what the source was. After lowering the flaps; we noticed that the center flap track slid down away from the aircraft attach point to the opening in the flap for the attach point inside the flap. Also; we noticed that the bolts that attach the flap track to the aircraft showed signs of failure. Maintenance control was notified; and they fixed the flap. The next morning the captain and myself maintenance ferried the aircraft back to ZZZ. Callback conversation with reporter revealed the following information: the reporter stated the fuel leak was discovered on a preflight inspection and when the flaps were lowered to find the leak; it was obvious the inboard trailing edge flap was loose and the attach bolts had failed. The flap track was rptedly replaced overnight and the airplane was ferried to another station. The reporter stated the scheduled flight; the day the fuel leak was discovered; was canceled. Supplemental information from acn 674369: we noticed a 1 inch by approximately 4 inch long gash in the bottom wing panel aft of the left main landing gear. After further inspection; we concluded that the only thing that could have done this was the flaps. We lowered the flaps and found that the middle flap track arm had sheared at the attachment point. The result was the arm was free to move in several directions. Last retraction or possibly a previous retraction the arm had contacted the bottom of the wing had caused the damage.

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Original NASA ASRS Text

Title: DURING PREFLT INSPECTION OF A B737-300; THE FO FOUND A FUEL LEAK UNDER THE L WING. AFTER LOWERING THE FLAPS; MAINT FOUND THE INBOARD CENTER FLAP TRACK LOOSE. THE ATTACH BOLTS HAD FAILED ALLOWING THE MIDDLE FLAP TRACK ARM TO MOVE FREELY. CONTACT WITH THE BOTTOM WING PANEL RESULTED IN A ONE INCH BY FOUR INCH GASH IN THE PANEL.

Narrative: AFTER PERFORMING INITIAL COCKPIT FLOWS AND SETUP; I PROCEEDED TO THE EXTERIOR INSPECTION OF MY PREFLT. UPON ARRIVING AT THE L SIDE OF THE ACFT; I NOTICED A SMALL FUEL LEAK. I THEN PROCEEDED BACK TO THE FLT DECK TO NOTIFY THE CAPT AND HAVE HIM INSPECT IT TOO. WHILE LOOKING FOR THE SOURCE OF THE LEAK; WE NOTICED A SMALL (APPROX 1/16 INCH) IMPRESSION IN THE PHENOLIC PANEL JUST INBOARD OF THE L INBOARD TRAILING EDGE FLAP. WHEN THE MECHANIC ARRIVED; HE ASKED US TO LOWER THE FLAPS SO HE COULD INSPECT WHAT THE SOURCE WAS. AFTER LOWERING THE FLAPS; WE NOTICED THAT THE CTR FLAP TRACK SLID DOWN AWAY FROM THE ACFT ATTACH POINT TO THE OPENING IN THE FLAP FOR THE ATTACH POINT INSIDE THE FLAP. ALSO; WE NOTICED THAT THE BOLTS THAT ATTACH THE FLAP TRACK TO THE ACFT SHOWED SIGNS OF FAILURE. MAINT CTL WAS NOTIFIED; AND THEY FIXED THE FLAP. THE NEXT MORNING THE CAPT AND MYSELF MAINT FERRIED THE ACFT BACK TO ZZZ. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE RPTR STATED THE FUEL LEAK WAS DISCOVERED ON A PREFLT INSPECTION AND WHEN THE FLAPS WERE LOWERED TO FIND THE LEAK; IT WAS OBVIOUS THE INBOARD TRAILING EDGE FLAP WAS LOOSE AND THE ATTACH BOLTS HAD FAILED. THE FLAP TRACK WAS RPTEDLY REPLACED OVERNIGHT AND THE AIRPLANE WAS FERRIED TO ANOTHER STATION. THE RPTR STATED THE SCHEDULED FLT; THE DAY THE FUEL LEAK WAS DISCOVERED; WAS CANCELED. SUPPLEMENTAL INFO FROM ACN 674369: WE NOTICED A 1 INCH BY APPROX 4 INCH LONG GASH IN THE BOTTOM WING PANEL AFT OF THE L MAIN LNDG GEAR. AFTER FURTHER INSPECTION; WE CONCLUDED THAT THE ONLY THING THAT COULD HAVE DONE THIS WAS THE FLAPS. WE LOWERED THE FLAPS AND FOUND THAT THE MIDDLE FLAP TRACK ARM HAD SHEARED AT THE ATTACHMENT POINT. THE RESULT WAS THE ARM WAS FREE TO MOVE IN SEVERAL DIRECTIONS. LAST RETRACTION OR POSSIBLY A PREVIOUS RETRACTION THE ARM HAD CONTACTED THE BOTTOM OF THE WING HAD CAUSED THE DAMAGE.

Data retrieved from NASA's ASRS site as of January 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.